1. Field of the Invention
Apparatuses and methods consistent with the present invention relate to an oscillator tuning system and an oscillator tuning method which enables a backscatter link frequency (BLF) of a radio frequency identification (RFID) oscillator to be within a range of a threshold by distinguishing where there is abundant energy, i.e. a near field region, from where there is less abundant energy, i.e. a far field region and operating the RFID oscillator at a driving frequency according to the distinguished regions.
2. Description of Related Art
An RFID tag is a type of a transponder device that can respond to being read by sending contents of its embedded memory by backscatter communication to an interrogator, i.e. a reader. A passive RFID tag has no bakery; instead, it gets all the needed energy to send a signal to the reader from a carrier signal of the reader.
When an oscillator within the RFID tag is operated using a driving frequency of 1.28 MHz, a backscatter link frequency of the oscillator according to ‘PC Gen. 2 Spec.’ is out of some part of the range of a threshold. Accordingly, power consumption may be reduced. However, it is not easy to stably process a signal of an oscillator within an RFID tag being operated using a driving frequency of 1.28 MHz.
In order to address the above problem, an oscillator operating method, which is performed by increasing the driving frequency, is provided. However, the method has a problem in that power consumption is so great that good performance may not be guaranteed when processing the signal of the RFID tag in a long distance environment, despite the fact a backscatter link frequency (BLF) of the RFID oscillator may be within a range of the threshold in all regions by operating the oscillator using a higher frequency of 1.92 MHz.
Therefore, a new tuning model for an RFID oscillator is needed which can adjustably process the signal of the RFID tag in all regions, and smoothly process the RFID tag in a long distance environment by adaptively tuning the driving frequency of the RFID oscillator.